Polycyclic ether antibiotic having anthelmintic, anticoccidial and growth promotant activity

Abstract

An acidic polycyclic ether antibiotic, having structure established by X-ray crystallography, is formed by fermentation of a novel microorganism, Streptomyces sp. ATCC 55028. This novel antibiotic is useful as an anticoccidial in chickens, in the prevention or treatment of swine dysentery, as a growth promotant in cattle and swine, and as an anthelmintic in mammals, particularly in dogs, cats, sheep, cattle and swine.

We claim: 
     
       1. A biologically pure culture of Streptomyces sp. ATCC 55028, said culture being capable of producing the compound having the formula ##STR2## in a recoverable quantity upon fermentation in an aqueous nutrient medium comprising assimilable sources of carbon and nitrogen. 
     
     
       2. The culture of claim 1 in freeze-dried form.